Sonographic B-lines Research Articles

Prognostic Role of Sonographic Decongestion in Patients with Acute Heart Failure with Reduced and Preserved Ejection Fraction: A Multicentre Study.

We investigated the role of the dynamic changes of pulmonary congestion, as assessed by sonographic B-lines, as a tool to stratify prognosis in patients admitted for acute heart failure with reduced and preserved ejection fraction (HFrEF, HFpEF). In this multicenter, prospective study, lung ultrasound was performed at admission and before discharge by trained investigators, blinded to clinical findings. We enrolled 208 consecutive patients (mean age 76 [95% confidence interval, 70-84] years), 125 with HFrEF, 83 with HFpEF (mean ejection fraction 32% and 57%, respectively). The primary composite endpoint of cardiovascular death or HF re-hospitalization occurred in 18% of patients within 6 months. In the overall population, independent predictors of the occurrence of the primary endpoint were the number of B-lines at discharge, NT-proBNP levels, moderate-to-severe mitral regurgitation, and inferior vena cava diameter on admission. B-lines at discharge were the only independent predictor in both HFrEF and HFpEF subgroups. A cut-off of B-lines > 15 at discharge displayed the highest accuracy in predicting the primary endpoint (AUC = 0.80, p < 0.0001). Halving B-lines during hospitalization further improved event classification (continuous net reclassification improvement = 22.8%, p = 0.04). The presence of residual subclinical sonographic pulmonary congestion at discharge predicts 6-month clinical outcomes across the whole spectrum of acute HF patients, independent of conventional biohumoral and echocardiographic parameters. Achieving effective pulmonary decongestion during hospitalization is associated with better outcomes.

Trajectory of pulmonary congestion by lung ultrasound in patients with acute myocardial infarction and association with cardiac structure and function

Abstract Background The PARADISE-MI trial examined the efficacy of sacubitril/valsartan in patients with acute myocardial infarction (AMI) complicated by reduced left ventricular ejection fraction (LVEF), pulmonary congestion or both. Little is known about the trajectory and echocardiographic correlates of pulmonary congestion in this population. Purpose We sought to assess the trajectory of pulmonary congestion using lung ultrasound (LUS) and its association with cardiac structure and function in a subset of patients enrolled in PARADISE- MI. Methods Participants underwent 8-zone LUS at baseline and 8 months. B-lines were quantified offline, blinded to treatment group, clinical findings, timepoint and outcomes by a core laboratory. Paired t-tests, chi-squared tests, and linear regression analyses were conducted. Results Among 152 patients (median age 65 years, 32% women, 35% obese, mean LVEF 41%), any B-lines were detectable in 87%, the median sum of B-lines in 8 zones was 4 [IQR 2–8], and 67% had ≥3 B-lines indicative of congestion. Greater number of B-lines at baseline was associated with larger left atrial (LA) size, higher E/e' and E/A ratios, greater degree of mitral regurgitation, worse right ventricular (RV) systolic function, and higher tricuspid regurgitation velocity (P trend &amp;lt;0.05 for all) (Figure 1). Among 115 patients with 8-month LUS data, there was a significant decline in number of B-lines from baseline (mean ± SD: −1.6±7.3; p=0.018). Adjusted for baseline, B-lines at follow-up were on average 6 (95% CI: 3, 9) higher in a patient who experienced an intercurrent heart failure (HF) event than a non-HF patient (p=0.001). Among 75 patients with ≥3 B-lines at baseline, a decrease in B-lines to &amp;lt;3, indicating decongestion, occurred in 37% and was similar in the sacubitril/valsartan and ramipril groups (36% vs. 39%, p=0.83). Conclusions In this post-AMI cohort, sonographic B-lines, indicating pulmonary congestion, were common at baseline and were significantly higher at follow-up in those who developed HF. Worse pulmonary congestion at baseline was associated with prognostically important echocardiographic markers of LV filling pressure, pulmonary pressure, and RV function. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Novartis

Optimizing Lung Ultrasound: The Effect of Depth, Gain and Focal Position on Sonographic B-Lines.

Ultrasonographic B-lines are artifacts present in alveolar-interstitial syndromes. We prospectively investigated optimal depth, gain, focal position and transducer type for B-line visualization and image quality. B-Lines were assessed at a single rib interspace with curvilinear and linear transducers. Video clips were acquired by changing parameters: depth (6, 12, 18 and 24 cm for curvilinear transducer, 4 and 8 cm for linear transducer), gain (10%, 50% and 90%) and focal position (at the pleural line or half the scanning depth). Clips were scored for B-lines and image quality. Five hundred sixteen clips were obtained and analyzed. The curvilinear transducer improved B-line visualization (63% vs. 37%, p < 0.0001), with higher image quality (3.52 ± 0.71 vs. 3.31 ± 0.86, p=0.0047) compared with the linear transducer. B-Lines were better visualized at higher gains (curvilinear: gain of 50% vs. 10%, odds ratio=7.04, 95% confidence interval: 4.03-12.3; gain of 90% vs. 10%, odds ratio=9.48, 95% confidence interval: 5.28-17.0) and with the focal point at the pleural line (odds ratio=1.64, 95% confidence interval: 1.02-2.63). Image quality was highest at 50% gain (p=0.02) but decreased at 90% gain (p < 0.0001) and with the focal point at the pleural line (p < 0.0001). Image quality was highest at depths of 12-18 cm. B-Lines are best visualized using a curvilinear transducer with at least 50% gain and focal position at the pleural line. Gain less than 90% and image depth between 12 and 18 cm improve image quality.

Meta-Analysis of Point-of-Care Lung Ultrasonography Versus Chest Radiography in Adults With Symptoms of Acute Decompensated Heart Failure

Acute decompensated heart failure (ADHF) is a primary cause of older adults presenting to the emergency department with acute dyspnea. Point-of-care lung ultrasound (LUS) has shown comparable or superior diagnostic accuracy in comparison with a chest x-ray (CXR) in patients presenting with symptoms of ADHF. The systematic review and meta-analysis aimed to elucidate the sensitivity and specificity of LUS in comparison with CXR for diagnosing ADHF and summarize the rapidly growing body of evidence in this domain. A total of 5 databases were searched through February 18, 2021, to identify observational studies that reported on the use of LUS compared with CXR in diagnosing ADHF in patients presenting with shortness of breath. Meta-analysis was conducted on the sensitivities and specificities of each diagnostic method. A total of 8 studies reporting on 2,787 patients were included in this meta-analysis. For patients presenting with signs and symptoms of ADHF, LUS was found to be more sensitive than CXR (91.8% vs 76.5%) and more specific than CXR (92.3% vs 87.0%) for the detection of cardiogenic pulmonary edema. In conclusion, LUS is more sensitive and specific than CXR in detecting pulmonary edema. This highlights the importance of sonographic B-lines, along with the accurate interpretation of clinical data, in the diagnosis of ADHF. In addition to its convenience, reduced costs, and reduced radiation exposure, LUS should be considered an effective alternative to CXR for evaluating patients with dyspnea in the setting of ADHF.

Bedside lung ultrasonography by emergency department residents as an aid for identifying heart failure in patients with acute dyspnea after a 2-h training course

BackgroundUltrasonographic B-lines have recently emerged as a bedside imaging tool for the differential diagnosis of acute dyspnea in the Emergency Department (ED). However, despite its simplicity, LUS has not fully penetrated emergency department. This study aimed to assess the accuracy and reproducibility of ultrasonographic B-lines performed by emergency medicine (EM) residents for the diagnosis of congestive heart failure (CHF) in patients admitted to ED for acute dyspnea.Patients and methodsThis is a cross-sectional prospective study conducted between January 2016 and October 2017 including patients aged over 18 years admitted to ED for acute dyspnea. At admission, two consecutive bedside LUS study were performed by a pair of EM residents who received a 2-h course for recognition of sonographic B-lines to determine independently B-lines score and B-profile pattern. All participating sonographers were blinded to patients’ clinical data. B-lines score ≥ 15 or a B-profile pattern was considered as suggestive of CHF. The final leading diagnosis was assessed by two expert sonographers, who were blinded to the residents’ interpretations, based on clinical findings, chest X-ray, brain natriuretic peptide, cardiac and lung ultrasound testing. Accuracy and agreement of B-lines score and B-profile pattern were calculated.ResultsWe included 700 patients with a mean age of 68 ± 12.6 years and a sex ratio (M/F) of 1.43. The diagnosis of CHF was recorded in 371 patients (53%). The diagnostic performance of B-lines score at a cut-off 15 and B-profile pattern was, respectively, 88% and 82.5% for sensitivity, 75% and 84% for specificity, 80% and 85% for positive predictive value, 84% and 81% for negative predictive value. The area under receiver operating characteristic curve was 0.86 [0.83–0.89] and 0.83 [0.80–0.86], respectively, for B-lines score and B-profile pattern. There was an excellent agreement between residents for the diagnosis of CHF using both scores (kappa = 0.81 and 0.85, respectively, for ordinal scale B-lines score and B-profile pattern).ConclusionLung ultrasound B-lines assessment has a good accuracy and an excellent reproducibility in the diagnosis of CHF in the hand of EM residents following a short training program.Trial registration Name of the registry: clinicaltrials.gov; Trial registration number: NCT03717779; Date of registration: October 24, 2018 ‘Retrospectively registered’; URL of trial registry record: clinicaltrials.gov

Prognostic role of sonographic decongestion in patients with acute heart failure with reduced and preserved ejection fraction: a multicentre study

Abstract Aims Our aim was to assess the dynamic changes of pulmonary congestion (PC) through variations of sonographic B-lines, in addition to conventional clinical, biohumoral and echocardiographic findings, to improve prognostic stratification of patients admitted for acute heart failure with reduced and preserved ejection fraction (HFrEF, HFpEF). Methods In this multicenter, prospective, observational study, lung ultrasound was performed in all patients at admission and before discharge by trained investigators, blinded to clinical findings and outcomes. Results We enrolled 208 consecutive patients admitted for acute heart failure (125 HFrEF, 83 HFpEF, mean age 75.9±11.7 years, 36% females, mean ejection fraction 38%). After 180-day follow-up, 38 composite endpoint events occurred (cardiovascular deaths or HF re-hospitalisations). In a multivariate model, B-lines at discharge had independent prognostic value in the overall population together with NT-proBNP, moderate-to-severe mitral regurgitation (MR) and inferior vena cava diameter at admission. When dividing the population in HFrEF and HFpEF, B-lines at discharge was the only independent parameter to predict events in all subgroups. At ROC analysis, a cut-off of B-lines&amp;gt;15 at discharge displayed the highest accuracy in predicting adverse events (AUC=0.80, p&amp;lt;0.0001). The identification of patients unable to halve B-lines during hospitalization (ΔB-lines%), in addition to B-lines &amp;gt;15 at discharge, improved event classification (integrated discrimination improvement=4%, p=0.01; continuous net reclassification improvement=22.8%, p=0.04). Conclusions The presence of residual subclinical sonographic PC at discharge predicts adverse events in the whole spectrum of acute HF patients, independently of conventional biohumoral and echocardiographic parameters. The dynamic evaluation of pulmonary decongestion during hospital stay can further improve patient risk stratification. Funding Acknowledgement Type of funding source: None

Abstract 346: A Trial of Pre-discharge Point of Care Ultrasound for Acute Decompensated Heart Failure

Background: Acute decompensated heart failure (ADHF) is a primary reason for hospital admission and readmission in the elderly. Prior studies have demonstrated that sonographic pulmonary B-lines and large inferior vena cava (IVC) diameter with reduced collapsibility may accurately predict ADHF readmission. Ultrasound is a readily available bedside tool that can be used to assess a patient’s volume status, which can be difficult to assess under certain clinical conditions. The purpose of this project is to determine if a pre-discharge focused lung and IVC ultrasound exam can be used to predict readmission in a veteran patient population. Methods: This is a single-center study conducted at the Miami Veterans Affair Medical Center (VAMC). Only patients with a primary diagnosis of ADHF admitted to a hospitalist team through the emergency room will be considered. Exclusion criteria include: pre-existing structural lung disease; primary right-sided heart failure; severe tricuspid regurgitation; or hospice status. A single operator will evaluate all included patients for B-lines and IVC dimension within 24 hours of admission and discharge. Ultrasound results, without management recommendations, will be given to hospitalists to use at their discretion to support clinical decision-making. Patients will be categorized based on positive or negative ultrasound findings. The primary outcome of interest is 30-day readmission rate. Secondary outcomes include 90-day readmission, all-cause mortality, length of stay, and changes in weight or renal function. Chi-square and Mann-Whitney testing will be used to analyze categorical and continuous variables, respectively. Kaplan-Meier survival curves will be generated for both patient cohorts. Results/Anticipated Results: Through quarter 3 of fiscal year 2019, the Miami VAMC had 215 unique admissions for ADHF. The average 30-day readmission rate per quarter was 18.44% (total 40 of 215). Study enrollment is ongoing. We anticipate that many patients may demonstrate discrepancy of volume status between their clinical and ultrasound exams, and that patients found to have B-lines and/or large IVCs with poor collapsibility will have worse outcomes. Conclusion: Decreasing readmissions for acute decompensated heart failure is a priority for both patients and physicians. Persistent volume overload has been associated with increased risk for readmission. Ultrasound may be a useful augmentation to the physical exam to determine a patient’s volume status to further guide inpatient treatment, predict prognosis, and determine readiness for discharge.

The haemodynamic basis of lung congestion during exercise in heart failure with preserved ejection fraction

Increases in extravascular lung water (EVLW) during exercise contribute to symptoms, morbidity, and mortality in patients with heart failure and preserved ejection fraction (HFpEF), but the mechanisms leading to pulmonary congestion during exercise are not well-understood. Compensated, ambulatory patients with HFpEF (n = 61) underwent invasive haemodynamic exercise testing using high-fidelity micromanometers with simultaneous lung ultrasound, echocardiography, and expired gas analysis at rest and during submaximal exercise. The presence or absence of EVLW was determined by lung ultrasound to evaluate for sonographic B-line artefacts. An increase in EVLW during exercise was observed in 33 patients (HFpEFLW+, 54%), while 28 (46%) did not develop EVLW (HFpEFLW-). Resting left ventricular function was similar in the groups, but right ventricular (RV) dysfunction was two-fold more common in HFpEFLW+ (64 vs. 31%), with lower RV systolic velocity and RV fractional area change. As compared to HFpEFLW-, the HFpEFLW+ group displayed higher pulmonary capillary wedge pressure (PCWP), higher pulmonary artery (PA) pressures, worse RV-PA coupling, and higher right atrial (RA) pressures during exercise, with increased haemoconcentration indicating greater loss of water from the vascular space. The development of lung congestion during exercise was significantly associated with elevations in PCWP and RA pressure as well as impairments in RV-PA coupling (area under the curve values 0.76-0.84). Over half of stable outpatients with HFpEF develop increases in interstitial lung water, even during submaximal exercise. The acute development of lung congestion is correlated with increases in pulmonary capillary hydrostatic pressure that favours fluid filtration, and systemic venous hypertension due to altered RV-PA coupling, which may interfere with fluid clearance. NCT02885636.

Transthoracic sonographic assessment of B-line scores during ascent to altitude among healthy trekkers

Sonographic B-lines can indicate pulmonary interstitial edema. We sought to determine the incidence of subclinical pulmonary edema measured by sonographic B-lines among lowland trekkers ascending to high altitude in the Nepal Himalaya. Twenty healthy trekkers underwent portable sonographic examinations and arterial blood draws during ascent to 5160 m over ten days. B-lines were identified in twelve participants and more frequent at 4240 m and 5160 m compared to lower altitudes (P < 0.03). There was a strong negative correlation between arterial oxygen saturation and the number of B-lines at 5160 m (ρ = −0.75, P = 0.008). Our study contributes to the growing body of literature demonstrating the development of asymptomatic pulmonary edema during ascent to high altitude. Portable lung sonography may have utility in fieldwork contexts such as trekking at altitude, but further research is needed in order to clarify its potential clinical applicability.

Bedside sonography assessment of extravascular lung water increase after major pulmonary resection in non-small cell lung cancer patients.

Extra vascular lung water (EVLW) following pulmonary resection increases due to fluid infusion and rises in capillary surface and permeability of the alveolar capillary membranes. EVLW increase clinically correlates to pulmonary oedema and it may generate impairments of gas exchanges and acute lung injury. An early and reliable assessment of postoperative EVLW, especially following major pulmonary resection, is useful in terms of reducing the risk of postoperative complications. The currently used methods, though satisfying these criteria, tend to be invasive and cumbersome and these factors might limit its use. The presence and burden of EVLW has been reported to correlate with sonographic B-line artefacts (BLA) assessed by lung ultrasound (LUS). This observational study investigated if bedside LUS could detect EVLW increases after major pulmonary resection. Due to the clinical association between EVLW increase and impairment of gas exchange, secondary aims of the study included investigating for associations between any observed EVLW increases and both respiratory ratio (PaO2/FiO2) and fluid retention, measured by brain natriuretic peptide (BNP). Overall, 74 major pulmonary resection patients underwent bedside LUS before surgery and at postoperative days 1 and 4, in the inviolate hemithorax which were divided into four quadrants. BLA were counted with a four-level method. The respiratory ratio PaO2/FiO2 and fluid retention were both assessed. BLA resulted being increased at postoperative day 1 (OR 9.25; 95% CI, 5.28-16.20; P<0.0001 vs. baseline), and decreased at day 4 (OR 0.50; 95% CI, 0.31-0.80; P=0.004 vs. day 1). Moreover, the BLA increase was associated with both increased BNP (OR 1.005; 95% CI, 1.003-1.008; P<0.0001) and body weight (OR 1.040; 95% CI, 1.008-1.073; P=0.015). Significant inverse correlations were observed between the BLA values and the PaO2/FiO2 respiratory ratios. Our results suggest that LUS, due to its non-invasiveness, affordability and capacity to detect increases in EVLW, might be useful in better managing postoperative patients.

Evaluating Extravascular Lung Water in Sepsis: Three Lung-Ultrasound Techniques Compared against Transpulmonary Thermodilution.

Background:Excessive extravascular lung water (EVLW) is associated with increased morbidity and mortality. We compared three lung-ultrasound (L-US) techniques against the reference-standard transpulmonary thermodilution (TPTD) technique to access EVLW.Materials and Methods:This was a prospective, single-blind, cross-sectional study. Forty-four septic patients were enrolled. EVLW index was measured by the TPTD method, and an index of ≥10 mL/kg was considered diagnostic of pulmonary edema. EVLW index was then compared to three established bedside L-US protocols that evaluate sonographic B-lines: (1) a 28-zone protocol (total B-line score [TBS]) (2) a scanning 8-region examination, and (3) a 4-point examination.Results:Eighty-nine comparisons were obtained. A statistically significant positive correlation was found between L-US TBS and an EVLW index ≥10 mL/kg (r = 0.668,P < 0.001). The 28-zone protocol score ≥39 has a sensitivity of 81.6% and a specificity of 76.5% to define EVLW index ≥10 mL/kg. In contrast, the positive 4-point examination and scanning 8-regions showed low sensitivity (23.7% and 50.0%, respectively) but high specificity (96.1% and 88.2%, respectively). Ten patients with a total of 21 comparisons met criteria for acute respiratory distress syndrome (ARDS). In this subgroup, only the TBS had statistically significant positive correlation to EVLW (r = 0.488,P = 0.025).Conclusion:L-US is feasible in patients with severe sepsis. In addition, L-US 28-zone protocol demonstrated high specificity and better sensitivity than abbreviated 4- and 8-zone protocols. In ARDS, the L-US 28-zone protocol was more accurate than the 4- and 8-zone protocols in predicting EVLW. Consideration of limitations of the latter protocols may prevent clinicians from reaching premature conclusions regarding the prediction of EVLW.Trial Registration:ISRCTN11419081. Registered 4 February 2015 retrospectively.

Use of lung ultrasonography to determine the accuracy of clinically estimated dry weight in chronic hemodialysis patients

The use of lung ultrasound (LUS) to identify extravascular lung water has received increasing acceptance. Sonographic B-lines, discrete vertical lines that originate from the pleura, represent pulmonary edema and are correlated with the accumulation of fluid. The goal of this study was to evaluate the utility of LUS to determine the accuracy of prescribed dry weight (DW) in chronic hemodialysis (HD) patients and to ascertain the adequacy of fluid removal. LUS was scheduled to be performed pre- and post-HD in 20 patients. The HD prescription and DW challenge were done independent of the results of the LUS. The presence of B-lines was tabulated and compared to the intradialytic ultrafiltration parameters. Of the 20 patients, 3 did not exhibit B-lines at the first dialysis session. In regard to the other 17 patients, B-lines disappeared in 7 patients at the end of the HD session (mean B-lines 4.2-0). One patient was 0.3kg away from the prescribed dry weight, but the 6 patients were a mean of 1.7kg below DW. Of the remaining 10 patients, eight decreased but did not eliminate the B-lines (mean B-lines 15.5-3.8) and were a mean of 3.8kg below DW post-HD. Two patients who exhibited more cardiac insufficiency than initially recognized could not reach DW or eliminate the B-lines. Eight patients who had residual B-lines at the end of the first HD session had their DW re-estimated and had a second session. Two were able to eliminate the B-lines (mean 2.5-0) and reached a mean of 1.2kg below DW. Six did not eliminate the B-lines (mean 11.5-4.2) but were able to reach a mean of 0.6kg below DW. Correlation analysis showed a statistically significant correlation (P<0.05) between the intradialytic percent change in B-lines and the percent change in total body weight (r=0.40) and ultrafiltration rate (r=0.33). Seven of 10 patients with clear chest X-rays pre-HD exhibited B-lines. This study supports the hypothesis that reduction in B-lines during HD can provide accurate information regarding changes in pulmonary fluid content. Further, LUS is a valuable diagnostic tool for recognizing both the adequacy of fluid removal and the occurrence of error in the estimation of dry weight by usual clinical parameters.

Resolution of sonographic B-lines as a measure of pulmonary decongestion in acute heart failure

Objective noninvasive measures of dyspnea in patients with acute heart failure are lacking. In this review, we describe lung ultrasound as a tool to estimate the degree of pulmonary congestion in patients presenting with acute heart failure and to monitor therapeutic efficacy. Serial semiquantitative measures of sonographic B-lines in acute heart failure patients can be converted to pulmonary edema scores obtained at admission and hospital discharge. These scores provide prognostic information for short-term clinical outcomes. Lung ultrasound has the potential to measure changes in pulmonary edema during acute heart failure management and improve risk stratification.

Interobserver agreement in the evaluation of B-lines using bedside ultrasound

PurposeWe evaluated agreement among trained emergency physicians assessing the degree of B-line presence on bedside ultrasound in patients presenting to the emergency department (ED) with acute undifferentiated dyspnea. We also determined which thoracic zones offered the highest level of interobserver reliability for sonographic B-line assessment. Materials and methodsWe evaluated a prospective convenience sample of adult patients presenting with dyspnea to an academic ED. Two consecutive bedside lung ultrasounds were performed on 91 patients by a pair of physician-sonographers. The lung ultrasounds were structured 10-zone thoracic sonograms, documented as videos. Sonographer pairs were expert/expert (>100 lung ultrasounds performed) or expert/novice pairs (novices performed 5 supervised examinations after structured training) and blinded to clinical data. Sonographers reported B-line concentration with 3 assessment methods: (1) normal (<3 B-lines) or abnormal (≥3 B-lines); (2) ordinal (normal, mild, moderate, or severe), and (3) counting B-lines (0-10; >10) in each zone. All statistical analyses were performed using SPSS version 18.0 (Chicago, IL) and Stata 12.1 (College Station, TX). We evaluated interrater and intrarater agreement using Intraclass correlation coefficients (ICCs). ResultsThe right and left anterior/superior lung zones showed substantial agreement in all assessment methods and demonstrated best overall agreement (ICC for right: counting, ordinal, and normal/abnormal, 0.811 [0.714-0.875], 0.875 [0.810-0.917], and 0.729 [0.590-0.821], respectively). Furthermore, both expert/expert pairs and expert/novice pairs showed substantial agreement in the right and left anterior/superior thoracic zones (expert/expert, 0.904 and 0.777, respectively; expert/novice, 0.862, and 0.834, respectively). Second best agreement was found for the lateral/superior lung zones (right: counting, ordinal, and normal/abnormal, 0.744 [0.612-0.831], 0.686 [0.524-0.792], and 0.639 [0.453-0.761], respectively; and ICC left: counting, ordinal, and normal/abnormal, 0.671 [0.501-0.782], 0.615 [0.417-0.746], and 0.720 [0.577-0.815], respectively). When comparing agreement to distinguish “normal vs abnormal” B-line findings, our results showed significant agreement in all zones with the exception of the right and left inferior/lateral lung fields and left posterior lung. Reinterpretation by 2 experts of all their own randomized video clips at a later date showed agreement of 0.697 (n = 733 zones) and 0.647 (n = 266) zones for ordinal assessment of B-line concentration. ConclusionInterrater agreement was best in the anterior/superior thoracic zones followed by the lateral/superior zones for both expert/expert and expert/novice pairs. Agreement in the lateral/inferior lung zones was overall inferior. Intrarater agreement was highest at extreme high or low numbers of B-lines.

B-lines: Transthoracic chest ultrasound signs useful in assessment of interstitial lung diseases.

OBJECTIVE:This prospective study was conducted to evaluate the value of sonographic B-lines (previously called “comet tail artifacts”), which are long, vertical, well-defined, hyperechoic, dynamic lines originating from the pleural line in assessment of interstitial lung diseases (ILD) and compare them with the findings of chest high-resolution computed tomography (HRCT) and pulmonary function tests (PFTs).MATERIALS AND METHODS:Sixty-one patients with ILD underwent transthoracic lung ultrasound for assessment of the presence of B-lines and the distance between them. These findings were compared with that of chest HRCT (ground glass, reticular, nodular or honey combing) and PFT as forced vital capacity (FVC), total lung capacity (TLC), diffusion capacity for carbon monoxide (DLCO) and partial arterial oxygen pressure (PaO2).RESULTS:All patients had diffuse bilateral B-lines. The distance between each of the two adjacent B lines correlated with the severity of the disease on chest HRCT where B3 (the distance was 3 mm) correlated with ground glass opacity and B7 (the distance was 7 mm) correlated with extensive fibrosis and honey combing. Also, the distance between B-lines inversely correlated with FVC (r = −0.848, P < 0.001), TLC (r = −0.664, P < 0.001), DLCO (r = −0.817, P < 0.001) and PaO2 (r = −0.902, P < 0.001).CONCLUSION:B-lines that are lung Ultrasound signs seem to be useful in the assessment of ILD.

Echocardiographic and Lung Ultrasound Characteristics in Ambulatory Patients with Dyspnea or Prior Heart Failure

Lung ultrasound (LUS) represents a novel, noninvasive method in the assessment of extravascular lung water. We investigated the utility of LUS in ambulatory subjects with dyspnea or prior heart failure (HF). We studied 81 ambulatory subjects with HF history or dyspnea who underwent transthoracic echocardiography (TTE) with LUS of 8 zones. Subjects with heart transplantation or pulmonary conditions known to interfere with LUS were excluded. A reviewer blinded to the clinical data performed echocardiographic measurements and quantified B-lines (reverberation artifacts arising from the pleural line). Of 81 subjects, 74 (91%) (median age 66 years, 39% men, median left ventricular ejection fraction [LVEF] 54%, 39% with prior HF) had adequate LUS images of all 8 zones and were included in the analysis. The number of B-lines ranged from 0-12 (median 2). Increased B-lines, analyzed by tertiles, were associated with larger left ventricular (LV) end-diastolic (P = 0.036) and end-systolic diameters (P = 0.026), septal wall thickness (P = 0.009), LV mass index (P = 0.001), left atrial (LA) volume index (P = 0.005), tricuspid regurgitation (TR) velocity (P = 0.005) and estimated pulmonary artery systolic pressure (PASP) (P = 0.003). In a secondary analysis associations between B-lines (not grouped by tertiles) and LV mass index, LA volume index, TR velocity and PASP remained stable after adjustment for age, gender, BMI and HF history. Sonographic B-lines from LUS are related to measures of LV and LA structure and right ventricular pressure in ambulatory patients with dyspnea or prior HF. The added clinical and prognostic utility of this imaging modality in ambulatory patients warrants further investigation.

Inter-Rater Reliability of Quantifying Pleural B-Lines Using Multiple Counting Methods

Sonographic B-lines are a sign of increased extravascular lung water. Several techniques for quantifying B-lines within individual rib spaces have been described, as well as different methods for "scoring" the cumulative B-line counts over the entire thorax. The interobserver reliability of these methods is unknown. This study examined 3 methods of quantifying B-lines for inter-rater reliability. Videotaped pleural assessments of adult patients presenting to the emergency department with dyspnea and suspected acute heart failure were reviewed by 3 blinded pairs of emergency physicians. Each pair performed B-line counts within single rib spaces using 1 of the following 3 predetermined methods: 1, individual B-lines are counted over an entire respiratory cycle; 2, as per method 1, but confluent B-lines are counted as multiple based on the percentage of the rib space they occupy; and 3, as per method 2, but the count is made at the moment when the most B-lines are seen, not over an entire respiratory cycle. A single-measures interclass correlation coefficient was used to assess inter-rater reliability for the 3 definitions of B-line counts. A total of 456 video clips were reviewed. The interclass correlation coefficients (95% confidence intervals) for methods 1, 2, and 3 were 0.84 (0.81-0.87), 0.87 (0.85-0.90), and 0.89 (0.87-0.91), respectively. The difference between methods 1 and 3 was significant (P = .003). All methods of B-line quantification showed substantial inter-rater agreement. Method 3 is more reliable than method 1. There were no other significant differences between the methods. We recommend the use of method 3 because it is technically simpler to perform and more reliable than method 1.

Test characteristics of thoracic point of care ultrasonography for the diagnosis of acute congestive heart failure in the emergency department

The test characteristics of thoracic Point of Care Ultrasonography (PoCUS) for the diagnosis of acute congestive heart failure (CHF) are not well known, and no prior study evaluated the diagnostic impact of pleural effusions. We sought to determine the test characteristics of thoracic PoCUS when performed within 2 hours of initial emergency physician (EP) assessment by combining sonographic B-lines and pleural effusion to diagnose acute CHF.

Utility of lung ultrasound in predicting pulmonary and cardiac pressures

Quantification of linear lung ultrasound (LUS) artefacts (B-lines) represents a novel, non-invasive approach to assess pulmonary congestion. We investigated the relationship between the number of B-lines (vertical artefacts arising from the pleural line) and intracardiac pressures. Prior to scheduled right heart catheterization (RHC), 100 subjects underwent LUS of eight zones. A reviewer blinded to the haemodynamic data quantified the number of sonographic B-lines. Of 92 subjects who completed RHC, 79 had adequate LUS data of all zones [median age 61 years, 26 women, median left ventricular ejection fraction (LVEF) 58%, 35 with history of heart failure; 22 postcardiac transplantation]. The number of B-lines correlated with measured right atrial (r = 0.32), pulmonary artery diastolic (PADP) (r = 0.34), mean pulmonary artery (mPAP) (r = 0.43), pulmonary artery systolic (PASP) (r = 0.48) pressures, and pulmonary vascular resistance (PVR) (r = 0.51) (P < 0.005 for all), but not with pulmonary capillary wedge pressure. There was a graded association between tertiles of B-line number and increasing PADP, mPAP, PASP, and PVR (P for trend ≤0.001 for all). Each additional B-line was associated with an increase in PASP of 1 mmHg and an increase in PVR of 0.1 Wood units. These associations remained robust after multivariable adjustment (P = 0.002). Assessment of two inferior lateral zones resulted in similar correlations to the eight-zone method. Easily obtainable, LUS may be useful in the estimation of right-sided cardiac pressures and PVR. Further evaluation of lung ultrasound as an adjunct to heart failure diagnosis, monitoring, and prognosis is warranted.

Transthoracic ultrasound assessment of B-lines for identifying the increment of extravascular lung water in shock patients requiring fluid resuscitation

Sonographic B-lines are commonly observed in cases of increasing extravascular lung water (EVLW). These findings became prominent when interstitial and alveolar tissues were filled with fluid [1,2]. Thus, we hypothesized that the increment of sonographic B-lines would be observed when the EVLW increased after fluid resuscitation in shock patients and be associated with the impaired gas exchange.